Damping structure for a rotor assembly of a motor

ABSTRACT

A damping structure for a rotor assembly includes holes defined in a rotor and in a side board respectively and damping elements inserted into the holes of the rotor to be located between the rotor and the side board. Each damping element is received in a corresponding to one of the holes of the rotor and the side board so as to absorb vibration from the rotor to the axle of the rotor assembly.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a damping structure, and more particularly to a damping structure for a rotor assembly of a motor so that the vibration of the rotor assembly resulted from the high frequency resonance of current is reduced.

2. Description of the Prior Art

A rotor assembly and an axle of a motor are two isolated parts. When the axle is extended into the rotor assembly, there is no connector sandwiched therebetween. Therefore, when the rotor assembly is rotated due to the induced current from the variation of magnetic field, the rotation of the rotor assembly is not smooth due to the high frequency resonance of the induced current. As such, the operation of the axle generates noises and may even cause hazardous resonance. Adding damping elements between the rotor assembly and the axle does do the job of reducing the noise. However, the damping elements are complicated and expensive

To overcome the shortcomings, the present invention tends to provide an improved damping structure to mitigate the aforementioned problems.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide a damping structure for a rotor assembly of a motor to damp out the vibration caused by the high frequency resonance of current.

In one aspect of the present invention, the damping structure of the present invention includes multiple first holes defined in a rotor, second holes defined through side boards respectively mounted on opposite sides of the rotor and damping elements sandwiched between the side board and the rotor each damping element provided with third holes aligned with the second holes of the side board and the first holes of the rotor so that after the axle is extended through the side boards, the damping elements and the rotor, positioning pins are able to extend through the aligned first holes, second holes and the third holes to secure engagement between the side boards and the rotor.

A further objective of the present invention is that the damping element is a rubber ring and the third holes are defined in the rubber ring.

Still a further objective of the present invention is that the positioning pins are made of rubber so that the positioning pins are able to directly extended into the aligned first holes and the second holes to secure engagement between the rotor and the side boards and to damp away the vibration caused by the operation of the rotor.

Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic side plan view showing parts of the damping structure of the present invention to be applied to a rotor assembly which has an axle extending through the damping assembly;

FIG. 2 is a schematic cross sectional view showing the assembly of the damping structure with the rotor assembly; and

FIG. 3 is a cross sectional view taken from line 3-3 of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to FIGS. 1 and 2, it is noted that the damping structure in accordance with the present invention is applied to a rotor assembly including a rotor (2) incorporated with an axle (1) extending through the rotor (2). A side board (3) is provided on opposite sides of the rotor (2) to secure the axle (1) inside the rotor (2). The damping structure of the present invention includes first holes (21) defined in the rotor (2), second holes (31) defined in each of the side boards (3) and third holes (61) defined in damping elements (6) which are sandwiched between the side board (3) and the rotor (2). In addition, positioning pins (5) are provided to extend through the side board, the damping element (6) and the rotor (2) to secure position of the damping elements (6) between the side board (3) and the rotor (2).

With reference to FIG. 2, it is noted that the second holes (31) are aligned with the third holes (61) which in turn align with the first holes (21) such that the positioning pins (5) are able to extend through the aligned first holes (21), the second holes (31) and the third holes (61) to assemble the rotor assembly after the axle (1) is first extended through the side board (3), the damping element (6) and the rotor (2). Preferably, the damping element (6) in this embodiment is a rubber sleeve inserted into a corresponding one of the first holes (21) of the rotor (2). Preferably, a quantity of the first holes is between 2˜60. Furthermore, the positioning pins (5) may be made of metal or rubber. When the positioning pins (5) are made of rubber, it is noted that the damping element (6) may be omitted.

With reference to FIG. 3, it is noted that the rubber sleeves are interconnected via a rubber ring and the third holes (61) are still defined in the rubber sleeves to allow the extension of the positioning pins (5) into the rotor (2).

As a consequence of the provision of the damping structure to the rotor assembly, it is noted that when the outer rotor (2) is rotated and vibrated due to the high frequency resonance from the current, because the damping structure, i.e. the rubber sleeves (6) in the first holes (21) of the rotor (2), exists between the rotor (2) and the side boards (3), the vibration from the rotor (2) is effectively damped so that the force transmitted to the axle (1) is smooth and thus noise generated by the axle (1) is effectively reduced.

It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

1. A damping structure for a rotor assembly having a rotor and an axle extending through the rotor, the damping structure comprising: first holes adapted to be defined in the rotor; a first side board provided on one side of the rotor and the first side board having second holes in communication with the first holes of the rotor; damping elements sandwiched between the first side board and the rotor and each damping element having third holes in communication with the first holes of the rotor; and positioning pins extending through the second holes of the first side board, the third holes of the damping elements and the first holes of the rotor to secure position of the damping elements between the side board and the rotor such that vibration caused by rotation of the rotor is effectively reduced.
 2. The damping structure as claimed in claim 1, wherein the damping elements include a plurality of rubber sleeves respectively inserted into a corresponding one of the first holes of the rotor.
 3. The damping structure as claimed in claim 2 further comprising a second side board provided to sandwich the damping elements with the rotor and being opposite to the first side board in relation to the rotor.
 4. The damping structure as claimed in claim 1 further comprising a rubber ring interconnecting the damping elements.
 5. The damping structure as claimed in claim 2 further comprising a rubber ring interconnecting the damping elements.
 6. The damping structure as claimed in claim 3 further comprising a rubber ring interconnecting the damping elements.
 7. The damping structure as claimed in claim 3, wherein a quantity of the first holes is between 2˜60.
 8. The damping structure as claimed in claim 4, wherein a quantity of the holes is between 2˜60.
 9. The damping structure as claimed in claim 5, wherein a quantity of the holes is between 2˜60.
 10. The damping structure as claimed in claim 6, wherein a quantity of the holes is between 2˜60. 